The present invention relates generally to work machines, and more particularly to control systems for work machines with reorientable seat assemblies.
Engineers often seek strategies to reduce fuel consumption, noise, and pollution while not compromising the performance of a work machine. Work machines often include one or more hydraulically-controlled implements. For instance, a backhoe includes a loader and a digging implement. In order to operate the backhoe, hydraulic pressure is supplied to at least one hydraulic cylinder via a hydraulic pump that is powered by an engine. Thus, when the backhoe is being operated while the work machine is stationary, the operator may need to increase the engine speed in order to power the hydraulic pump and operate the backhoe. The operator may increase the engine speed by moving a throttle, usually a hand controller, from a throttle setting corresponding with a low idle engine speed to a throttle setting corresponding with an increased engine speed. However, when the operator stops using the backhoe, and the implement becomes idle or stationary, the throttle will remain at the setting corresponding with the increased engine speed until the operator moves the throttle back to the setting corresponding with the low idle engine speed.
Work machines such as the backhoe shown in U.S. Pat. No. 5,025,770 issued to Richardson on Jun. 25, 1991, conserve fuel and reduce noise and pollution by including an apparatus that reduces engine speed below the increased throttle setting when the implements, illustrated as the backhoe and a loader, have been idled for a predetermined time period and the transmission is not engaged. Although the Richardson apparatus may reduce fuel consumption by reducing engine speed when the backhoe is idle, the Richardson apparatus does not address at least some of the effects the engine speed reduction apparatus may have on the operation of a second set of equipment that could be attached to the work machine body. For instance, the work machine may have the backhoe attached to the rear side of the work machine body and a second set of equipment, such as a loader, attached to the front side of the work machine body. The Richardson apparatus operates similarly regardless of whether the operator is operating the backhoe or the loader. However, because the loader is generally used for shoveling material, the operator will often drive the work machine while operating the loader. Thus, when operating the loader, the transmission will be engaged, and the operator will control the engine speed with a second throttle controller, such as a foot pedal. When the operator no longer depresses the foot pedal, the engine speed should return to a low idle speed. Therefore, a method of reducing engine speed after the predetermined time of idling the loader may not be necessary.
Further, allowing the engine speed reduction apparatus to reduce the engine speed below the throttle setting regardless of which implement is enabled may result in undesirable movement of the work machine. For example, after the operator has ceased using the backhoe, the engine speed reduction apparatus may override the throttle setting and reduce the engine speed to the predetermined low idle speed. When the operator rotates his seat and engages the transmission to operate the loader, the engine speed may jump back up to the throttle setting, possibly causing the work machine to lurch forward. In addition, the Richardson apparatus appears to reduce engine speed mechanically, resulting in an increased number of moving work machine components.
The present invention is directed to overcoming one or more of the problems set forth above.
In one aspect of the present invention, a work machine includes a work machine body and an electronic control module including an engine speed reduction algorithm. A set of equipment is attached to the work machine body. A seat assembly is rotatably mounted to the work machine body and is movable between a first position and a second position. When the seat assembly is in the first position, the engine speed reduction algorithm is inactive, and when the seat assembly is in the second position, the engine speed reduction algorithm is active.
In another aspect of the present invention, a control system for use in a work machine includes a seat assembly position sensor that is in communication with an engine speed reduction algorithm of an electronic control module. The engine speed reduction algorithm is inactive when the electronic control module determines that a seat assembly is in a first position, and the engine speed reduction algorithm is active when the electronic control module determines that the seat assembly is in a second position.
In yet another aspect of the present invention, there is a method of operating a work machine. An engine speed reduction algorithm is activated, at least in part, when an operator rotates a seat assembly to a second position. The engine speed is reduced below a throttle setting via the engine speed reduction algorithm, at least in part, when the operator idles a set of equipment for a predetermined period of time.